/* =============================================
   障害年金サポートセンター - Main Stylesheet
   ============================================= */

/* 1. Variables */
:root {
  --primary: #1B3F7A;
  --primary-dark: #122B5A;
  --primary-light: #2A5BAD;
  --accent: #F0932B;
  --accent-dark: #D47A1A;
  --accent-light: #FFB347;
  --success: #27AE60;
  --bg: #F4F7FB;
  --bg-dark: #E8EDF5;
  --white: #FFFFFF;
  --text: #1A1A2E;
  --text-gray: #5A6278;
  --text-light: #8892A4;
  --border: #D0D9E8;
  --shadow-sm: 0 2px 8px rgba(27,63,122,0.08);
  --shadow-md: 0 4px 20px rgba(27,63,122,0.12);
  --shadow-lg: 0 8px 40px rgba(27,63,122,0.16);
  --radius: 12px;
  --radius-sm: 8px;
  --radius-lg: 20px;
  --transition: 0.25s ease;
  --font: 'Noto Sans JP', 'Hiragino Kaku Gothic ProN', 'Meiryo', sans-serif;
}

/* 2. Reset & Base */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; font-size: 16px; }
body {
  font-family: var(--font);
  color: var(--text);
  background: var(--bg);
  line-height: 1.75;
  -webkit-font-smoothing: antialiased;
}
img { max-width: 100%; height: auto; display: block; }
a { color: inherit; text-decoration: none; }
ul, ol { list-style: none; }

/* 3. Typography */
h1, h2, h3, h4 { font-weight: 900; line-height: 1.35; }
h1 { font-size: clamp(1.75rem, 5vw, 2.75rem); }
h2 { font-size: clamp(1.5rem, 4vw, 2.25rem); }
h3 { font-size: clamp(1.2rem, 3vw, 1.5rem); }
h4 { font-size: 1.1rem; }
p { line-height: 1.85; }

/* 4. Layout */
.container {
  width: 100%;
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 20px;
}
.container--narrow { max-width: 780px; }
.section {
  padding: 80px 0;
}
.section--bg { background: var(--white); }
.section--dark { background: var(--primary); color: var(--white); }

.section-label {
  display: inline-block;
  font-size: 0.8rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  color: var(--accent);
  background: rgba(240,147,43,0.1);
  padding: 4px 14px;
  border-radius: 100px;
  margin-bottom: 14px;
  text-transform: uppercase;
}
.section-title {
  color: var(--primary);
  margin-bottom: 16px;
}
.section-title span { color: var(--accent); }
.section-sub {
  color: var(--text-gray);
  font-size: 1.05rem;
  max-width: 560px;
  margin: 0 auto 48px;
}
.text-center { text-align: center; }

/* 5. Header */
.header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background: var(--white);
  box-shadow: var(--shadow-sm);
}
.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 70px;
  gap: 20px;
}
.logo {
  display: flex;
  flex-direction: column;
  gap: 1px;
}
.logo-main {
  font-size: 1.1rem;
  font-weight: 900;
  color: var(--primary);
  line-height: 1.2;
}
.logo-sub {
  font-size: 0.68rem;
  color: var(--text-gray);
  letter-spacing: 0.05em;
}
.logo-accent { color: var(--accent); }

.nav { display: none; }
.nav-list {
  display: flex;
  align-items: center;
  gap: 4px;
}
.nav-link {
  display: block;
  padding: 8px 14px;
  font-size: 0.9rem;
  font-weight: 700;
  color: var(--text);
  border-radius: var(--radius-sm);
  transition: var(--transition);
}
.nav-link:hover, .nav-link.active { color: var(--primary); background: var(--bg); }

.header-cta {
  display: none;
}
.header-cta .btn-sm {
  padding: 10px 20px;
  font-size: 0.9rem;
}

.hamburger {
  display: flex;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 44px;
  height: 44px;
  cursor: pointer;
  border: none;
  background: none;
  padding: 6px;
  border-radius: var(--radius-sm);
  transition: var(--transition);
}
.hamburger span {
  display: block;
  width: 100%;
  height: 2.5px;
  background: var(--primary);
  border-radius: 2px;
  transition: var(--transition);
  transform-origin: center;
}
.hamburger.open span:nth-child(1) { transform: translateY(7.5px) rotate(45deg); }
.hamburger.open span:nth-child(2) { opacity: 0; transform: scaleX(0); }
.hamburger.open span:nth-child(3) { transform: translateY(-7.5px) rotate(-45deg); }

/* Mobile drawer */
.nav-drawer {
  display: none;
  position: fixed;
  inset: 70px 0 0;
  background: var(--white);
  z-index: 999;
  padding: 20px;
  overflow-y: auto;
  animation: slideDown 0.25s ease;
}
.nav-drawer.open { display: block; }
.nav-drawer .nav-list { flex-direction: column; align-items: stretch; gap: 4px; }
.nav-drawer .nav-link { padding: 14px 16px; font-size: 1rem; border-bottom: 1px solid var(--border); border-radius: 0; }
.nav-drawer .btn { display: block; margin-top: 16px; text-align: center; }

@keyframes slideDown {
  from { opacity: 0; transform: translateY(-10px); }
  to { opacity: 1; transform: translateY(0); }
}

/* 6. Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 16px 32px;
  font-family: var(--font);
  font-size: 1rem;
  font-weight: 700;
  border: none;
  border-radius: var(--radius);
  cursor: pointer;
  transition: var(--transition);
  text-align: center;
}
.btn-primary {
  background: var(--accent);
  color: var(--white);
  box-shadow: 0 4px 16px rgba(240,147,43,0.35);
}
.btn-primary:hover {
  background: var(--accent-dark);
  transform: translateY(-2px);
  box-shadow: 0 6px 24px rgba(240,147,43,0.45);
}
.btn-outline {
  background: transparent;
  color: var(--white);
  border: 2px solid rgba(255,255,255,0.6);
}
.btn-outline:hover { background: rgba(255,255,255,0.15); border-color: var(--white); }
.btn-outline-primary {
  background: transparent;
  color: var(--primary);
  border: 2px solid var(--primary);
}
.btn-outline-primary:hover { background: var(--primary); color: var(--white); }
.btn-lg { padding: 18px 40px; font-size: 1.1rem; }
.btn-sm { padding: 10px 20px; font-size: 0.9rem; }
.btn-full { width: 100%; }
.btn-icon { font-size: 1.1em; }

/* 7. Hero */
.hero {
  background: linear-gradient(135deg, var(--primary-dark) 0%, var(--primary) 50%, var(--primary-light) 100%);
  color: var(--white);
  padding: 80px 0 60px;
  position: relative;
  overflow: hidden;
}
.hero::before {
  content: '';
  position: absolute;
  top: -50%;
  right: -20%;
  width: 70%;
  height: 200%;
  background: radial-gradient(circle, rgba(240,147,43,0.12) 0%, transparent 60%);
  pointer-events: none;
}
.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: rgba(240,147,43,0.2);
  border: 1px solid rgba(240,147,43,0.4);
  color: var(--accent-light);
  font-size: 0.85rem;
  font-weight: 700;
  padding: 6px 16px;
  border-radius: 100px;
  margin-bottom: 24px;
}
.hero-title {
  font-size: clamp(1.8rem, 6vw, 3.2rem);
  font-weight: 900;
  line-height: 1.25;
  margin-bottom: 20px;
}
.hero-title .accent { color: var(--accent-light); }
.hero-desc {
  font-size: clamp(1rem, 2.5vw, 1.15rem);
  color: rgba(255,255,255,0.85);
  margin-bottom: 36px;
  max-width: 540px;
}
.hero-btns {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-bottom: 48px;
}
.hero-note {
  font-size: 0.8rem;
  color: rgba(255,255,255,0.6);
  margin-top: 12px;
}
.hero-stats {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
  max-width: 480px;
}
.hero-stat {
  background: rgba(255,255,255,0.1);
  border: 1px solid rgba(255,255,255,0.15);
  border-radius: var(--radius);
  padding: 16px 12px;
  text-align: center;
}
.hero-stat-num {
  font-size: clamp(1.6rem, 4vw, 2rem);
  font-weight: 900;
  color: var(--accent-light);
  line-height: 1.1;
}
.hero-stat-label {
  font-size: 0.75rem;
  color: rgba(255,255,255,0.75);
  margin-top: 4px;
}

/* 8. Problem section */
.problem-list {
  display: grid;
  grid-template-columns: 1fr;
  gap: 14px;
  max-width: 600px;
  margin: 0 auto;
}
.problem-item {
  display: flex;
  align-items: center;
  gap: 14px;
  background: var(--white);
  padding: 18px 22px;
  border-radius: var(--radius);
  box-shadow: var(--shadow-sm);
  border-left: 4px solid var(--accent);
  font-size: 1rem;
  font-weight: 500;
}
.problem-icon {
  font-size: 1.5rem;
  flex-shrink: 0;
}

/* 9. Cards */
.card {
  background: var(--white);
  border-radius: var(--radius);
  box-shadow: var(--shadow-sm);
  overflow: hidden;
  transition: var(--transition);
}
.card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
}
.card-body { padding: 28px; }

.cards-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 20px;
}

.feature-card {
  background: var(--white);
  border-radius: var(--radius);
  padding: 28px;
  box-shadow: var(--shadow-sm);
  text-align: center;
  transition: var(--transition);
  border-top: 4px solid var(--primary);
}
.feature-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-md); }
.feature-icon {
  width: 64px;
  height: 64px;
  background: linear-gradient(135deg, var(--primary), var(--primary-light));
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.8rem;
  margin: 0 auto 18px;
  color: var(--white);
}
.feature-title {
  font-size: 1.1rem;
  font-weight: 900;
  color: var(--primary);
  margin-bottom: 10px;
}
.feature-desc {
  font-size: 0.9rem;
  color: var(--text-gray);
  line-height: 1.7;
}

/* 10. Steps */
.steps {
  display: grid;
  grid-template-columns: 1fr;
  gap: 0;
  position: relative;
}
.step {
  display: flex;
  gap: 20px;
  align-items: flex-start;
  padding: 0 0 36px;
  position: relative;
}
.step:last-child { padding-bottom: 0; }
.step::before {
  content: '';
  position: absolute;
  left: 22px;
  top: 44px;
  bottom: 0;
  width: 2px;
  background: linear-gradient(to bottom, var(--primary-light), var(--border));
}
.step:last-child::before { display: none; }
.step-num {
  width: 44px;
  height: 44px;
  background: linear-gradient(135deg, var(--primary), var(--primary-light));
  color: var(--white);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.1rem;
  font-weight: 900;
  flex-shrink: 0;
  box-shadow: 0 4px 12px rgba(27,63,122,0.3);
  position: relative;
  z-index: 1;
}
.step-body {}
.step-title {
  font-size: 1.05rem;
  font-weight: 900;
  color: var(--primary);
  margin-bottom: 6px;
  padding-top: 10px;
}
.step-desc {
  font-size: 0.9rem;
  color: var(--text-gray);
  line-height: 1.7;
}
.step-tag {
  display: inline-block;
  font-size: 0.75rem;
  font-weight: 700;
  color: var(--accent);
  background: rgba(240,147,43,0.1);
  padding: 2px 10px;
  border-radius: 100px;
  margin-bottom: 8px;
}

/* 11. Stats bar */
.stats-bar {
  background: var(--primary);
  padding: 40px 0;
}
.stats-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 24px;
}
.stat-item { text-align: center; }
.stat-num {
  font-size: clamp(2rem, 6vw, 3rem);
  font-weight: 900;
  color: var(--accent-light);
  line-height: 1;
}
.stat-unit { font-size: 1rem; }
.stat-label {
  font-size: 0.85rem;
  color: rgba(255,255,255,0.75);
  margin-top: 6px;
}

/* 12. FAQ Accordion */
.faq-list { display: flex; flex-direction: column; gap: 12px; }
.faq-item {
  background: var(--white);
  border-radius: var(--radius);
  box-shadow: var(--shadow-sm);
  overflow: hidden;
  border: 1px solid var(--border);
  transition: var(--transition);
}
.faq-item.open { border-color: var(--primary); }
.faq-q {
  display: flex;
  align-items: center;
  gap: 16px;
  padding: 20px 22px;
  cursor: pointer;
  user-select: none;
  font-weight: 700;
  font-size: 1rem;
  color: var(--text);
  transition: var(--transition);
}
.faq-q:hover { background: var(--bg); }
.faq-q-icon {
  width: 32px;
  height: 32px;
  background: var(--primary);
  color: var(--white);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.9rem;
  font-weight: 900;
  flex-shrink: 0;
}
.faq-item.open .faq-q-icon { background: var(--accent); }
.faq-q-text { flex: 1; }
.faq-toggle {
  font-size: 1.2rem;
  color: var(--primary);
  transition: transform 0.25s ease;
  flex-shrink: 0;
}
.faq-item.open .faq-toggle { transform: rotate(45deg); }
.faq-a {
  display: none;
  padding: 0 22px 20px 70px;
  font-size: 0.95rem;
  color: var(--text-gray);
  line-height: 1.8;
}
.faq-item.open .faq-a { display: block; }

/* 13. Case Cards */
.case-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 16px;
}
.case-card {
  background: var(--white);
  border-radius: var(--radius);
  padding: 22px;
  box-shadow: var(--shadow-sm);
  border-left: 5px solid var(--primary);
  transition: var(--transition);
}
.case-card:hover { transform: translateY(-2px); box-shadow: var(--shadow-md); }
.case-header {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 14px;
  flex-wrap: wrap;
}
.case-tag {
  font-size: 0.78rem;
  font-weight: 700;
  padding: 3px 12px;
  border-radius: 100px;
}
.tag-blue { background: rgba(27,63,122,0.1); color: var(--primary); }
.tag-orange { background: rgba(240,147,43,0.15); color: var(--accent-dark); }
.tag-green { background: rgba(39,174,96,0.12); color: #1E8449; }
.case-grade {
  font-size: 0.85rem;
  font-weight: 900;
  color: var(--accent-dark);
}
.case-body { font-size: 0.9rem; color: var(--text-gray); margin-bottom: 12px; }
.case-amount {
  display: flex;
  align-items: center;
  gap: 8px;
}
.case-amount-label { font-size: 0.8rem; color: var(--text-light); }
.case-amount-num {
  font-size: 1.15rem;
  font-weight: 900;
  color: var(--success);
}
.case-filter {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 24px;
}
.filter-btn {
  padding: 7px 16px;
  font-size: 0.85rem;
  font-weight: 700;
  border: 2px solid var(--border);
  background: var(--white);
  color: var(--text-gray);
  border-radius: 100px;
  cursor: pointer;
  transition: var(--transition);
  font-family: var(--font);
}
.filter-btn:hover, .filter-btn.active {
  border-color: var(--primary);
  color: var(--primary);
  background: rgba(27,63,122,0.06);
}

/* 14. Fee Table */
.fee-card {
  background: var(--white);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-md);
  overflow: hidden;
  margin-bottom: 24px;
}
.fee-card-header {
  background: linear-gradient(135deg, var(--primary), var(--primary-light));
  color: var(--white);
  padding: 28px;
  text-align: center;
}
.fee-card-title { font-size: 1.3rem; font-weight: 900; margin-bottom: 8px; }
.fee-card-body { padding: 28px; }
.fee-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 14px 0;
  border-bottom: 1px solid var(--border);
  gap: 16px;
}
.fee-row:last-child { border-bottom: none; }
.fee-row-label { font-size: 0.9rem; color: var(--text-gray); }
.fee-row-val { font-size: 1rem; font-weight: 700; color: var(--text); }
.fee-highlight { color: var(--accent-dark); font-size: 1.1rem; }
.fee-zero { color: var(--success); }

/* 15. Contact Form */
.contact-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 32px;
}
.form-group { margin-bottom: 20px; }
.form-label {
  display: block;
  font-size: 0.9rem;
  font-weight: 700;
  color: var(--text);
  margin-bottom: 8px;
}
.form-label .required {
  color: var(--white);
  background: #E74C3C;
  font-size: 0.7rem;
  padding: 2px 6px;
  border-radius: 4px;
  margin-left: 6px;
}
.form-input, .form-textarea, .form-select {
  width: 100%;
  padding: 13px 16px;
  font-family: var(--font);
  font-size: 1rem;
  color: var(--text);
  background: var(--white);
  border: 2px solid var(--border);
  border-radius: var(--radius-sm);
  transition: var(--transition);
  appearance: none;
}
.form-input:focus, .form-textarea:focus, .form-select:focus {
  outline: none;
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(27,63,122,0.1);
}
.form-textarea { min-height: 140px; resize: vertical; line-height: 1.7; }
.form-note { font-size: 0.8rem; color: var(--text-light); margin-top: 6px; }

.contact-info-card {
  background: var(--white);
  border-radius: var(--radius);
  padding: 28px;
  box-shadow: var(--shadow-sm);
}
.contact-info-title {
  font-size: 1.1rem;
  font-weight: 900;
  color: var(--primary);
  margin-bottom: 20px;
  padding-bottom: 14px;
  border-bottom: 2px solid var(--border);
}
.contact-info-item {
  display: flex;
  gap: 14px;
  margin-bottom: 18px;
  align-items: flex-start;
}
.contact-info-icon {
  font-size: 1.2rem;
  color: var(--accent);
  flex-shrink: 0;
  width: 24px;
  text-align: center;
  padding-top: 2px;
}
.contact-info-text { font-size: 0.9rem; color: var(--text-gray); }
.contact-info-text strong { display: block; color: var(--text); font-weight: 700; }
.contact-guarantee {
  background: rgba(39,174,96,0.08);
  border: 1px solid rgba(39,174,96,0.2);
  border-radius: var(--radius-sm);
  padding: 14px 16px;
  margin-top: 20px;
  font-size: 0.88rem;
  color: #1E8449;
  font-weight: 700;
}

/* 16. Office Table */
.office-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.95rem;
}
.office-table tr { border-bottom: 1px solid var(--border); }
.office-table th {
  width: 30%;
  padding: 16px;
  text-align: left;
  font-weight: 700;
  color: var(--primary);
  background: rgba(27,63,122,0.04);
  vertical-align: top;
}
.office-table td {
  padding: 16px;
  color: var(--text-gray);
  vertical-align: top;
}

/* 17. About page */
.grade-cards {
  display: grid;
  grid-template-columns: 1fr;
  gap: 16px;
  margin: 28px 0;
}
.grade-card {
  background: var(--white);
  border-radius: var(--radius);
  padding: 24px;
  box-shadow: var(--shadow-sm);
  border-top: 5px solid var(--primary);
  text-align: center;
}
.grade-card.grade-1 { border-top-color: var(--accent); }
.grade-card.grade-2 { border-top-color: var(--primary-light); }
.grade-card.grade-3 { border-top-color: var(--success); }
.grade-label {
  font-size: 1.5rem;
  font-weight: 900;
  margin-bottom: 8px;
}
.grade-amount {
  font-size: 1.2rem;
  font-weight: 700;
  color: var(--accent-dark);
  margin-bottom: 8px;
}
.grade-desc { font-size: 0.85rem; color: var(--text-gray); line-height: 1.7; }

.condition-row {
  display: grid;
  grid-template-columns: 1fr;
  gap: 16px;
  margin: 24px 0;
}
.condition-item {
  background: var(--white);
  border-radius: var(--radius);
  padding: 22px;
  box-shadow: var(--shadow-sm);
}
.condition-num {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 32px;
  height: 32px;
  background: var(--primary);
  color: var(--white);
  border-radius: 50%;
  font-weight: 900;
  font-size: 0.9rem;
  margin-bottom: 12px;
}
.condition-title { font-weight: 900; color: var(--primary); margin-bottom: 6px; font-size: 1rem; }
.condition-desc { font-size: 0.88rem; color: var(--text-gray); line-height: 1.7; }

/* 18. CTA section */
.cta-section {
  background: linear-gradient(135deg, var(--primary-dark), var(--primary));
  color: var(--white);
  padding: 72px 0;
  text-align: center;
  position: relative;
  overflow: hidden;
}
.cta-section::before {
  content: '';
  position: absolute;
  bottom: -30%;
  left: -10%;
  width: 50%;
  height: 200%;
  background: radial-gradient(circle, rgba(240,147,43,0.1) 0%, transparent 60%);
}
.cta-title {
  font-size: clamp(1.5rem, 4vw, 2.2rem);
  margin-bottom: 12px;
  color: var(--white);
}
.cta-sub { color: rgba(255,255,255,0.8); margin-bottom: 36px; font-size: 1.05rem; }
.cta-btns { display: flex; flex-wrap: wrap; gap: 14px; justify-content: center; }

/* 19. Footer */
.footer {
  background: #0F2447;
  color: rgba(255,255,255,0.75);
  padding: 60px 0 28px;
}
.footer-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 36px;
  margin-bottom: 48px;
}
.footer-logo-main { font-size: 1.2rem; font-weight: 900; color: var(--white); margin-bottom: 6px; }
.footer-logo-sub { font-size: 0.8rem; color: rgba(255,255,255,0.5); }
.footer-desc { font-size: 0.88rem; line-height: 1.8; margin-top: 14px; }
.footer-nav-title { font-size: 0.85rem; font-weight: 900; color: var(--white); margin-bottom: 14px; letter-spacing: 0.05em; }
.footer-nav-list { display: flex; flex-direction: column; gap: 8px; }
.footer-nav-link { font-size: 0.88rem; color: rgba(255,255,255,0.65); transition: var(--transition); }
.footer-nav-link:hover { color: var(--accent-light); }
.footer-bottom {
  border-top: 1px solid rgba(255,255,255,0.1);
  padding-top: 24px;
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  justify-content: space-between;
  align-items: center;
  font-size: 0.8rem;
  color: rgba(255,255,255,0.4);
}

/* 20. Page hero */
.page-hero {
  background: linear-gradient(135deg, var(--primary-dark), var(--primary));
  color: var(--white);
  padding: 56px 0 48px;
  text-align: center;
}
.page-hero-title { color: var(--white); margin-bottom: 10px; }
.page-hero-sub { color: rgba(255,255,255,0.75); font-size: 1rem; }
.breadcrumb {
  display: flex;
  align-items: center;
  gap: 8px;
  justify-content: center;
  font-size: 0.82rem;
  color: rgba(255,255,255,0.55);
  margin-bottom: 18px;
}
.breadcrumb a { color: rgba(255,255,255,0.7); }
.breadcrumb a:hover { color: var(--white); }
.breadcrumb-sep { color: rgba(255,255,255,0.35); }

/* 21. Scroll to top */
.back-to-top {
  position: fixed;
  bottom: 28px;
  right: 20px;
  width: 48px;
  height: 48px;
  background: var(--primary);
  color: var(--white);
  border: none;
  border-radius: 50%;
  font-size: 1.3rem;
  cursor: pointer;
  box-shadow: var(--shadow-md);
  transition: var(--transition);
  display: flex;
  align-items: center;
  justify-content: center;
  opacity: 0;
  pointer-events: none;
  z-index: 900;
}
.back-to-top.visible { opacity: 1; pointer-events: auto; }
.back-to-top:hover { background: var(--primary-light); transform: translateY(-3px); }

/* 22. Animations */
.fade-in {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 0.55s ease, transform 0.55s ease;
}
.fade-in.visible { opacity: 1; transform: translateY(0); }
.fade-in-delay-1 { transition-delay: 0.1s; }
.fade-in-delay-2 { transition-delay: 0.2s; }
.fade-in-delay-3 { transition-delay: 0.3s; }

/* 23. Responsive - Tablet */
@media (min-width: 640px) {
  .cards-grid { grid-template-columns: repeat(2, 1fr); }
  .grade-cards { grid-template-columns: repeat(3, 1fr); }
  .condition-row { grid-template-columns: repeat(3, 1fr); }
  .stats-grid { grid-template-columns: repeat(4, 1fr); }
  .problem-list { grid-template-columns: repeat(2, 1fr); }
  .hero-stats { max-width: 100%; }
}

/* 24. Responsive - Desktop */
@media (min-width: 960px) {
  html { font-size: 17px; }
  .hamburger { display: none; }
  .nav { display: block; }
  .header-cta { display: block; }
  .nav-drawer { display: none !important; }

  .hero { padding: 100px 0 80px; }
  .hero-inner {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    align-items: center;
  }
  .hero-stats { max-width: none; }

  .cards-grid { grid-template-columns: repeat(3, 1fr); }
  .case-grid { grid-template-columns: repeat(2, 1fr); }
  .contact-grid { grid-template-columns: 1fr 380px; }
  .steps {
    grid-template-columns: repeat(4, 1fr);
    gap: 24px;
  }
  .step { flex-direction: column; padding-bottom: 0; }
  .step::before {
    top: 22px;
    left: 44px;
    right: -24px;
    width: auto;
    height: 2px;
    bottom: auto;
  }
  .step-title { padding-top: 14px; }

  .footer-grid { grid-template-columns: 2fr 1fr 1fr; }
}

@media (min-width: 1100px) {
  .case-grid { grid-template-columns: repeat(3, 1fr); }
}

/* Utility */
.mt-8 { margin-top: 8px; }
.mt-16 { margin-top: 16px; }
.mt-24 { margin-top: 24px; }
.mt-32 { margin-top: 32px; }
.mb-8 { margin-bottom: 8px; }
.mb-16 { margin-bottom: 16px; }
.mb-24 { margin-bottom: 24px; }
.mb-32 { margin-bottom: 32px; }
.text-accent { color: var(--accent-dark); }
.text-primary { color: var(--primary); }
.text-success { color: var(--success); }
.divider { border: none; border-top: 2px solid var(--border); margin: 32px 0; }
.badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 0.8rem;
  font-weight: 700;
  padding: 4px 12px;
  border-radius: 100px;
  background: rgba(27,63,122,0.08);
  color: var(--primary);
}